Surface active compositions



No Drawing. Filed Dec. 1, 1959,58. No. 856,367 15 Claims. (Cl. 260-461)This invention relates to the production of surface active compositions,and more particularly to an improved process for preparing surfaceactive compositions containing mixtures of primary and secondaryphosphate esters of hydroxylic organic compounds.

Hydroxylic organic compounds have been previously esterified with anumber of different phosphating agents including phosphoric acid, P H11and POCl and the like. While such processes have in some instancesproduced surface active compounds or compositions, they have beencommonly subject to a number of procedural disadvantages and/or havefailed to produce a surface active product having optimum properties forcertain end uses. Thus, the use of P001 as the phosphating agent yieldsproducts containing bound chlorine atoms, and in addition requirescareful manipulation to remove the HCl produced during the reaction.Further, the 'HCl raises problems of corrosion. The use of phosphoricacid or solutions of P 0 in phosphoric acid as phosphating agentgenerally yields inconsistent mixtures of different types of esters,including esters of pyrophosphoric acid, phosphoric acid, primary,secondary and tertiary phosphates, and the like. When P 0 has beenemployed, considerably greater molar ratios of the hydroxy compoundswere regarded as necessary to bring the solid P 0 into solution. 1

In the copending application of Leslie G. Nunn and Stanley H. Hesse,Serial No. 852,188, filed November 12, 1959, a process is disclosed forproducing phosphate esters of hydroxylic organic compounds, whichprocess is directed towards eliminating the abovementioneddisadvantages.

Said process broadly comprises reacting one mole of P 0 with 2 to 4.5moles of a nonionic surface active agent having the molecularconfiguration of a condensation product of at least one mole of ethyleneoxide with one mole of a compound containing at least 6 carbon atoms anda reactive hydrogen atom under substantially anhydrous conditions and ata temperature belowabout 110 C. This process does not require the use ofan excess of the hydroxylic organic compound (in this instance thedefined nonionic surface active agent), in order to bring the P 0 intosolution. Substantially no tertiary phosphate ester is formed by thisprocess and little or no P 0 remains in the composition. Depending uponthe particular ratio of P 0 to the nonionic surface active agentemployed, and the nature of such nonionic, the product may in someinstances contain some unreacted nonionic surface active agent which forcertain uses is actually advantageous.

For similar reasons, the proportions of secondary phosphateesterzprimary phosphate esterzfree nonionic in the products of thisinvention will in general fall within the range of about 20 to 45%secondary esterz30 to 80% primary ester:0 to 40% nonionic, byweight.

While the process disclosed in said application is highly effective, ithas been found that the products thus pro-, duced are somewhat coloredand that such products tend to become discolored or to darken onstorage. Uncolored or light colored products are required in many usesfor surface active agents and many formulators of such compositions,particularly liquid detergent compositions, have rigid colorspecification for the components of such foratent' 3,094,051 vPatentedOct. 10, 1961 ice mulations which require substantially colorless rawmaterials.

It is an object ofthis invention to provide a process for producingphosphate esters of nonionic surface active agents which will result inlighter colored or substantially colorless products. Another object ofthis invention is to improve the process disclosed in said copendingapplication whereby lighter colored or substantially colorless productsare formed. Still another object of this invention is the provision ofsuch a process which will result in phosphate ester products havingimproved stability to discoloration or darkening on storage. Otherobjects and advantages will appear as the description proceeds.

The attainment of the above objects is made possible by my discoverythat lighter colored or substantially colorless products are obtainedwhen the phosphation re action disclosed in said copending applicationis carried out in the presence of a small or catalytic amount of aphosphorus-containing compound selected from the group consisting ofhypophosphorous acid, salts of hypophosphorous acid, phosphorous acid,and salts and esters of phosphorous acid. More particularly, myinvention includes a process comprising reacting one mole of P 0 with 2to 4.5 moles of a nonionic surface active agent having the. molecularconfiguration of a condensation product of at least one mole of ethyleneoxide with one mole of a compound containing at least 6 carbon atoms anda reactive hydrogen atom, under substantially anhydrous conditions andat a temperature below about .110 C. in the presence of a small amountof one or a mixture of the aforementioned hypophosphorous or phosphorousacid compounds.

By the use of such compounds in the described phosphation reaction, ithas been found that an unexpected and substantial improvement in the(absence of) color of the products and the resistance of such productsto discoloration in storage is obtained. Products resulting from the useof the present invention generally have VCS (varnish color scale,Gardner scale, standards of 1933) values of at least one less thanproducts of the same process carried out in the absence of thehypophosphorous or phosphorous acid compound. Products hav ing a VCScolor of about 1 or less are thus made possible, as compared with VCScolors of from about 2 to 7 or more for products produced without theaid of the present invention. Further, the products of this inventionhave been found to resist discoloration or darkening even after storagefor three to six months.

Since this invention is applicable for the improvement of the inventiveprocess disclosed in said copending application, the entire subjectmatter of said copending application is incorporated herein by referencethereto. Stated otherwise, said application fully discloses nonionicsurface active agents employed as reactants in the phospha-- .tionreaction, the conditions of reaction, the manner of carrying out thereaction, and the products thus produced, all of which are employed inthe present process.

Briefly stated, the nonionic surface active agents em- I ployed asreactants in the present invention are well known in the art and aredisclosed along with suitable methodsffortheir preparation in numerouspatents and other publications. In general, they may be obtained bycondensing a polyglycol ether containing the required 5 alent condensedwith the reactive chain, will depend primarily'upon the particularcompound with which it is condensed. As a convenient rule of thumb, anamount of alkylene oxide or equivalent should be employed which willresult in a condensation product containing about 20 to 85% by weight ofcombined alkylene oxide. 'However, the optimum amount of alkylene oxidefor attainment of the desired hydrophobic-hydrophilic balance may themolecular configuration of a condensation product of at least one moleof an alkylene oxide, preferably ethylene oxide, with one mole of acompound containing at least 6 carbon atoms and a reactive. hydrogenatom are preferably polyoxyalkylene derivatives of alkylated andpolyalkylatedphenols, multi-branched chain primary aliphatic alcoholshaving the molecular configuration of an alcohol produced by the x0process from a polyolefin of at least 7 carbon atoms, and straight chainaliphatic alcohols of at least 10 carbon atoms. Examples of thesederivatives and other suitable nonionic surface active agents which maybe phosphated in accordance with the present invention are includedbelow. In this list, E0. means ethylene oxide and the number precedingsame refers to the number of moles thereof reacted with one mole of thegiven reactive hydrogen-containing compound.

N onylphenol+9-l 1 E0. Nonylphenol+2 E.O.

-Dinonylphenol+7 E.O.

Dodecylphenol+l8 E.O.

Castor oil+20 E.O.

Tall oil+18 E.O.

Oleyl alcohol+20 E.O.

Lauryl alcohol+4 E.O.

Lauryl alcohol-H5 E.O.

Hexadecyl alcohol+12 E.O.

Hexadecyl alcohol-[-20 E.O.

Octadecyl alcohol+20 E.O.

Oxo tridecyl alcohol:

(From tetrapropylene)+7 E.O. (From tetrapropylene) E.O. (Fromtetrapropylene) E.O.

Dodecyl mercaptan+9 E.O.

Soya bean oil amine-{-10 E.0.

Rosin amine+32 E.O.

Coconut fatty acid amine+7 E.O.

Cocoa fatty acid-H0 E.O.

Dodecylbenzene sulfonamide+ 10 ED.

Decyl sulfonamide+6 E.O.

Oleic acid+5 E.O.

Polypropylene glycol (30 oxypropylene units) +10 -E.O.

In carrying out the phosphation reaction in accordance with thisinvention, the P 0 is preferably added gradually, with vigorousagitation, to the nonionic surface active agent in liquid form. If thelatter agent is a solid at room temperature, it should be heated toabove its melting point. Addition of the nonionic surface active agentto the P 0 is inadvisable since this has been found to result in theformation of tar and the like and to prevent the reaction fromproceeding to completion. The reaction is exothermic and in some casescooling is necessary to prevent the temperature from going above about110 C. since this tends to produce discolored and darkened products. Thereaction proceeds continuously during addition of the P 0 and solutionthereof in the nonionic surface active agent, and is substantially 90%complete or more by the time all of the P 0 has been added. The fewparticles of solid P 0 remaining in the reaction medium may be removedat this point if time is of the essence, but it is preferred in theinterests of economy to allow the reaction to proceed for an 4 5 hoursor more at ambient temperatures up to about "C. until all of the P 0 hasdissolved indicating complete reaction between the reactants involved.Vigorous agitation during the reaction is highly desirable to facilitateand expedite completion of the reaction.

It is an advantageous feature of this invention that the P 0 may beemployed in dry, solid form as a granular powder or other finely dividedor particulate form, for reaction with the above defined nonionicsurface active agents. However, if desired, the P 0 may first bedispersed in an inert organic diluent such asbenzene, xylene, ether,pentane, or low and high boiling hydrocarbon fractions.

After completion of the reaction, the reaction mixture may be cooled anddischarged. If carried out under rigid anhydrous conditions the productshould consist of a mixture of the primary and secondary phosphateesters of the nonionic surface active agent combined, depending upon theproportions of reactants, in some instances with a small proportion ofunreacted nonionic surface active agent. Any small amount of waterpresent in the reaction mixture will result protanto in the formation.of some phosphoric acid in the product. The degree of esterification inthe product may be determined by potentiometric titration or bytitration with alkali to methyl orange and then to phenolphthalein.

As referred to above, the essence of my invention resides in theaddition to the reaction medium of a small amount of hypophosphorous orphosphorous acid compound. Generally, about 0.01 to 5% and preferablyabout 0.1 to 2% of such compound, based on the weight of the nonionicsurface active agent being phosphated is sufficient to provide thedesired improvements with respect to prevention of color degradation ofthe prodnets and improvement in resistance of the products to 'colordegradation in storage. Hypophosphorous acid and its alkali metal salts,e.g. sodium and potassium salts are generally preferred although anymetal, alkaline earth metal, ammonium or amine salt of hypophosphorousacid or phosphorous acid may be employed, in addition to phosphorousacid per so. When hypophosphorous acid is employed, it is preferred touse a 30 to 50% aqueous solution thereof although aqueous solutions ofthis acid and other of the water soluble hypophosphorous and phosphorousacid compounds may be employed in the form of aqueous solutions rangingin concentration from less than 5 up to 70% or more. It should be bornein mind that the reaction should be carried out under subs't'antiallyanhydrous conditions and accordingly the water introduced in suchsolutions should be held to a minimum.

The salts of hypophosphorous acid and phosphorous acid employed hereinmay be in their hydrated or dehydrated form. As examples of such salts,there may be mentioned aluminum, cadmium, sodium, potassium, lithium,calcium, strontium, barium, magnesium, ammonium, mono-, di-, andtri-methylamine, -ethylamine, -propyl'amine, -ethanolamine, and-propanolamine, pyridinyl, and morpholinyl phosphites andhypophosphites.

Esters of phosphorous acid may also be employed. These esters may bedescribed as mono-, di-, and trialkyl, -aryl, and -cyeloalkylphosphites. It will be understood that mixed esters are included. Assome specific examples of such esters in which the esterifying groupgenerally contains from about 1 to 20 carbon atoms, there may bementioned ethyl phosphite, lauryl phosphite, OX0 tridecyl phosphite (theesterifying alcohol having the molecular configuration of an alcoholproduced from tetra propylene or triisobutylene by the 0x0 process),stearyl phosphite, phenyl phosphite, cyclohexyl phosphite, thecorresponding diand tri-substituted phosphites, ethyl phenyl phosphite,ethyl diphenyl phosphite, lauryl cyclohexyl phosphite, dipropyl phenylphosphite, and the like.

In accordance with this invention, the hypophosphorous or phosphorousacid compound is preferably admixed with additional period of time whichmay range from /2 'to 75. fhc'non-ioni'c'surface active agent prior toadditionthe'reto of the P if desired, however, such compound may beadded simultaneously with the addition of the P 0 or, if anhydrous, maybe admixed with the P 0 prior to its addition to the nonionic surfaceactive agent. It Will accordingly be understood that the hypophosphorousor '6 measurable by this method the highest being 18. Products preparedwith the use of the additives referred to in the table sustained nochange in color after 3 to 6 months storage.

phosphorous acld compound or mixture thereof may be 5 It will beunderstood that all parts and proportlons added at the start of thereactionmr continuously, or ,m-g to 3 111 the PP claims y termittentlyas the reaction proceeds. weight unless otherwise indicated.

OH- 205 VCS Ex. Nonionic agent ionic parts Parts Additive color parts1-----. Nonylphenol+2 E.O 2, 288 284 Control 2 Cs mCs 4( 2 4)n0 9 (in 2,288 284 3. 4 Hypophosphorous acid (50%). 1 3 Nonylphenol+4 E.O 2,355 213Control 4 CrHCsH4(OC2H4)4OH 4 do 2, 355 213 4. 2 Hypophosphorous acid(50%). 1 5 Nonylphenol+6 E.0 484 47. 3 Control 4 C9H nOc 4(0C2 4)aOH 6do 484 47. 3 1. 0 Hypophosphorous acid (50%) 1 7 do 484 47. 3 0. 5Sodium hypophosphite 1 8 do 484 47. 3 2.0 Triphenyl phosphite 2 9Nonylphenol+10 E.O 1, 821 108 Control 4 D 19 fl 4( 2 -)10 1n rln l, 821108 7. 0 Hypophosphorous acid (30%). 1 11 Nonylphcnol+100 E.O 605 11.9Control 2 Cr mCs 4(OCzH4)1ooOH 1 2 do 605 11. 9 1. 2 Hypophosphorousacid (50%)- 1 13"--- Dinonyl hcnol+7 E.O 327 23. 6 Control 5 O1 saCs a(OC2H4)1OH V 14 do 327 23. 6 1 0 Hypophosphorous acid (30%). 1 15"---Dodecyzlfihenol+6 E.O 1,052 94.4 Control 4 C1 2aCc 4(0C2 4)sOH V 16 dn1, 052 94. 4 3.0 Hypophosphorous acid (50%)- 1 17-- 0x0 tn'decyl alcohol+3 13.0 166 23. 7 Control 7 C;3H21(0C2H4)20H 18 d0 166 23. 7 1.0Hypophosphorous acid (50%)- 2 1 1 166 23. 7 1.0 Phosphorous acid 220---..- Lauryl alcohol+4 E.O 724 71 Control 7 O12H25(OO2H4)40H 21 (ln724 71 1. 3 Hypophosphorous acid (50%) 1 1 From tetrapropylene by the0x0 process.

The products of this invention may be supplied in free unneutralizedform, or in the form of the partially or completely neutralized saltscontaining as cations alkali metals, alkaline earth metals, metals,ammonium and organic amines. Use in the form of such salts is in someinstances preferred or necessary, as for example when employed inalkaline surface active and other compositions. It is to be understoodthat such salts are to be regarded as the equivalent of the presentproducts in their free form. As examples of suitable cations, there maybe mentioned sodium, potassium, lithium, calcium, strontium, barium,magnesium, iron, tin, cadmium, aluminum, antimony chromium, manganese,mercury, nickel, silver, zinc, ammonium and aliphatic, alicyclic,aromatic, and heterocyclic organic amines such as the mono-, di-, andtri-methylamines, -ethylamines,-propylamines,-laurylamines,-stearylamines, -ethanolamines, propanolamines,- butanolamines,-hexanolamines,- cyclohexylamines, -phenylamines, pyridylamine,morpholinylamine, and the like.

The examples in the following table are only illustrative of the presentinvention and are not to be regarded as limitative. In each of theseexamples, the nonionic surface active agent is first charged to areactor equipped with an agitator. If the charge is solid at roomtemperature, it is heated to melt the same. The additive referred to inthe table is then added to and dissolved in the nonionic surface activeagent with vigorous agitation. The solid granular P 0 is then charged tothe reactor with vigorous agitation over a period ranging from about 5minutes to about 1 hour and usually about 15 minutes. After the initialexothermic reaction subsides, the reaction mixture is heated to 100 C.and held at this temperature for about 5 hours after which the mixtureis cooled and discharged. A sample of the reaction mixture is titratedwith alkali to methyl orange and then to phenolphthalein as a control onthe esterification.

I The VCS color readings are measured in the prescribed manner. Areading of one is the lowest color reading Thisinvention has beendisclosed with respect to certain preferred embodiments and there willbecome obvious to persons skilled in the art various modifications,equivalents or variations thereof Which are intended to be includedwithin the spirit and scope of this invention.

I claim:

1.- In a process comprising reacting 1 mole of P 0 with 2 to 4.5 molesof a nonionic surface active agent having the molecular configuration ofa condensation product of atleast one mole of ethylene oxide with onemole of a compound containing about 6 to 150 carbon atoms and a reactivehydrogen atom and selected from the group consisting of phenol, alkylphenols, aliphatic alcohols, fatty acids, fatty amines, fatty amides,rosin amines, long chain sulfonamides, long chain-substituted arylsulfonamides, and high molecular weight mercaptans under substantiallyanhydrous conditions and at a temperature below about C. down to aboutroom temperature, the improvement comprising carrying out the reactionin the presence of a small amount of a phosphorus-containing compoundselected from the group consisting of hypophosphorous acid, salts ofhypophosphorous acid, phosphorous acid, and salts and esters ofphosphorous acid.

2. A process as defined in claim 1 wherein said reactivehydrogen-containing compound is an alkyl phenol of at least 10' carbonatoms.

3. A process as defined in claim 1 wherein said reactivehydrogen-containing compound is a multi-branched chain primary aliphaticalcohol having the molecular configuration of an alcohol produced by the0x0 process from a polyolefin of at least 7 carbon atoms.

4. A process as defined in claim 1 wherein said reactivehydrogen-containing compound is a straight chain aliphatic alcohol of atleast 10 carbon atoms.

5. A process as defined in claim 1 wherein said phosphorus-containingcompound is hypophosphorous acid.

6. A process as defined in claim 1 wherein said phosphorus-containingcompound is sodium hypophosphite.

7. A process as defined in claim -1 wherein said phosphorus-containingcompound is phosphorous acid.

8. ,A process as defined in claim 1 wherein said phosphorus-containingcompound is triphenyl 'phosphite,

9. In a process comprising gradually adding with agitation one mole ofdry, solid P 0 to 2 to 4.5 moles of a nonionic surface active agenthaving the molecularconfiguration of a condensation product of at leastone mole of ethylene oxide with one mole of a compound containing about6 to 150 carbon-atoms and a reactive hydrogen atom and selected from thegroup consisting of phenol, alkyl phenols, aliphatic alcohols, fattyacids, fatty amines, fatty amides, rosin amines, long chainsulfonamides, long chain-substituted aryl sulfonamides, and highmolecular weight mercaptans, and allowing the phosphation to proceedunder substantially. anhydrous conditions and at a temperature belowabout 110 C. down to about room temperature, the improvement comprisingfirst dissolving in'the nouionic surface active agenta small amount of aphosphorus-containing compound selected from the group consisting ofhypophosphorous acid,

salts of hypophosphorous acid, phosphorous acid, and salts and esters ofphosphorous acid.

10. A process as defined in claim 9 wherein said reactivehydrogen-containing compound is an alkyl phenol of at least 10 carbonatoms.

11. A process as defined in claim 9 wherein said Ieac tivehydrogen-containing compoundis a multi-hranched chain primary aliphaticalcohol having the molecular configuration of an alcohol produced by the0x0 process from a polyolefin of at least 7 carbon atoms.

12. A process as defined in claim 9 wherein said compound is a straightchain aliphatic alcohol of at least 10 carbon atoms.

13. A process as defined in claim 9 wherein said phosphorus-containingcompound is hypophosphorous acid.

14, A process as defined in claim 9 wherein said phos- I ReferencesCited in the file of this patent FOREIGN PATENTS 1,139,717 France July4, 1957

1. IN A PROCESS COMPRISING REACTING 1 MOLE OF P2O5 WITH 2 TO 4.5 MOLESOF A NONIONIC SURFACE ACTIVE AGENT HAVING THE MOLECULAR CONFIGURATION OFA CONDENSATION PRODUCT OF AT LEAST ONE MOLE OF ETHYLENE OXIDE WITH ONEMOLE OF A COMPOUND CONTAINING ABOUT 6 TO 150 CARBON ATOMS AND A REACTIVEHYDROGEN ATOM AND SELECTED FROM THE GROUP CONSISTING OF PHENOL, ALKYLPHENOLS, ALIPHATIC ALCOHOLS, FATTY ACIDS, FATTY AMINES, FATTY AMIDES,ROSIN AMINES, LONG CHAIN SULFONAMIDES, LONG CHAIN-SUBSTITUTED ARYLSULFONAMIDES, AND HIGH MOLECULAR WEIGHT MERCAPTANS UNDER SUBSTANTIALLYANHYDROUS CONDITIONS AND AT A TEMPERATURE BELOW ABOUT 110* C. DOWN TOABOUT ROOM TEMPERATURE, THE IMPROVEMENT COMPRISING CARRYING OUT THEREACTION IN THE PRESENCE OF A SMALL AMOUNT OF A PHOSPHORUS-CONTAININGCOMPOUND SELECTED FROM THE GROUP CONSISTING OF HYPOPHOSPHOROUS ACID,SALTS OF HYPOPHOSPHOROUS ACID, PHOSPHOROUS ACID, AND SALTS AND ESTERS OFPHOSPHOROUS ACID.